In this work, we analyze data from three seismic sensors located at strategic locations inside the avalanche path (starting zone, flowing zone and run-out area) and one seismic sensor located in the opposite hillside of the avalanche path, at Vallée de la Sionne test site. Seismic data are correlated in time with GEODAR data. Specifically, the length and the time-frequency features of the seismic data are compared to the flow regimes and front positions recognized from GEODAR data. All observations are complemented with snow cover conditions along the path and before/after photographs. Our results show that seismic data contain relevant information about avalanche flow regimes and thus, can be used to infer characteristics of the avalanche dynamics. Furthermore, the complementarity of the two different measuring systems (seismic and GEODAR) allows us to validate the observations and to enhance the avalanche knowledge from different points of view.